2355

Stardates:

Stardate 40217.3: In what later became known as the Battle of Maxia, the USS Stargazer is attacked by an unknown vessel (later revealed to be Ferengi in origin). His ship severely damaged, CaptainJean-Luc Picard devises a maneuver that makes the Stargazer appear in two places at once, which allows him to destroy the alien vessel. This maneuver, accomplished by making a very short warp jump, is dubbed the "Picard Maneuver". Picard and his crew are subsequently forced to abandon the stricken Stargazer, limping through space in shuttlecraft for weeks before being rescued. (TNG: "The Battle")

Dr.Paul Manheim first devises his theory that if the consistency of time is altered, a doorway into another dimension will appear. He won't put it into practical use for nine years, though. (TNG: "We'll Always Have Paris")